Articles of hygiene of this type are known from Patent Application GB-A-2,161,059 and from other, more recent documents, for example Patent Applications EP-A-219,326, 243,013, 374,640 and 391,476.
An article of hygiene of this type exhibiting a rectangular general shape may incorporate two opposed side cutouts imparting a so-called anatomical or hour-glass shape to the article of hygiene. Such an article of hygiene, whether provided with such side cutouts or not, has, in its length direction, a rear part corresponding to a lengthwise end region, a front part corresponding to the other lengthwise end region and a crotch part corresponding to the intermediate region of the nappy of the diaper. In an article of hygiene of anatomical or hourglass shape, the crotch part has a width which is smaller than the front part and the rear part.
The side flaps with which the articles of hygiene according to the abovementioned prior documents are provided are intended to improve the general leakproofing of the article of hygiene in the crotch part, as well as the action of confining urine and faecal matter. These side flaps forming the side barrier effect are arranged on the inner face of the cover sheet, that is to say the face in contact with the user's skin, and are spaced transversely so as to extend substantially along the lengthwise edges of the article of hygiene. These side flaps can either be formed directly in the material of the cover sheet, as proposed by Patent Application GB-A-2,161,059, or may consist of tapes made of material which is permeable or impervious to liquids and which are fastened to the inner face of the cover sheet. In all cases these flaps are joined by one of their lengthwise edges, called the proximal edge, to the cover sheet, and, at their other lengthwise edge called the distal edge, that is to say their free edge, carry an elastic member consisting, for example, of one or a number of elastic threads or strands which are preferably attached by adhesive bonding in the stretched state to the flap. This elastic member may, for example, be arranged in a sheath or a gusset formed by folding back the lengthwise edge of the tape onto itself, at least over the middle part of the length of this tape, corresponding to the crotch region of the article of hygiene, it being possible for the elastic member to be fastened to the flap either over its whole length or only at its two ends. In both lengthwise end regions of the article of hygiene, the distal edges of the flaps are fastened to the cover sheet, for example by a transverse adhesive bonding line or strip, so that here the flaps are arranged flat on the cover sheet, the distal edges of the two opposed flaps pointing either inwards, that is to say towards each other, or outwards, that is to say away from each other.
The first solution presents problems when the proximal edges of the flaps, in case of an article of hygiene of anatomical or hourglass shape, are arranged above the absorbent pad in the narrower crotch part, insofar as the distal edges of the two opposed flaps are then too close to each other, and this limits the leakproofing and the action of confining urine and faecal matter in the case of articles of hygiene in which the absorbent pad is also narrower in this crotch part.
The solutions proposed by the other abovementioned prior documents generally consist in fastening the flaps so that, in the crotch part of the article of hygiene, their proximal edges are situated outside the side edges of the absorbent pad, that is to say in a region where the cover sheet is fastened to the support sheet. In this case, owing to the thickness of the absorbent pad, these flaps must be relatively large in height to be able to provide a satisfactory barrier effect and must be largely independent in relation to the remaining part of the article of hygiene (absorbent pad, outer support sheet, lengthwise elastic members fastened to the outer support sheet), and this increases the unit cost of the article of hygiene equipped with such side flaps.
It therefore appears that the solutions proposed hitherto are not entirely satisfactory.
The present document relates to an article of hygiene of the type defined above, particularly an article of hygiene of so-called anatomical or hourglass shape, with a narrower absorbent pad in the crotch part, in which the side flaps are designed so as to provide an optimal barrier effect at a reduced cost.
The disposable absorbent article of hygiene in accordance with the invention, especially a diaper, is of substantially rectangular general shape with opposed lengthwise edges and opposed transverse edges and comprises, from the outside inwards, a liquid-impervious support sheet, an absorbent pad arranged and fastened to the inner face of the support sheet, the dimensions of the pad being smaller than those of the support sheet, and a liquid-permeable cover sheet at least partially covering the inner face of the absorbent pad and fastened at least partially to the support sheet on the periphery of the absorbent pad. In addition, this article comprises lengthwise elastic members fastened in the stretched state to the support sheet, outside the lengthwise edges of the absorbent pad. Furthermore, the article comprises two transversely spaced side flaps arranged on the inner face of the cover sheet, substantially along the lengthwise edges of the article of hygiene, each of the said flaps having a proximal edge connected to the cover sheet and a distal edge comprising a stretched lengthwise elastic member. In addition, the article of hygiene comprises fastening means, in the vicinity of one of its transverse edges, in order to close the article of hygiene around a user's waist so that the article of hygiene defines a front part and a rear part corresponding respectively to the two end regions near the said opposed transverse edges of the article of hygiene, and a crotch part corresponding to the intermediate region situated between the two said end regions. According to the invention, each of the said side flaps is fastened to the cover sheet along its proximal edge, over the whole length of the article of hygiene, so that the said proximal edge is above the absorbent pad over the whole length of the article of hygiene, including in the crotch part. This flap is folded back onto itself over its whole length, and is fastened to the cover sheet in the end parts of the article of hygiene, so that its elasticised distal edge is substantially above its proximal edge over the whole length of the flap.
Thus, the proximal edge of each side flap is situated as close as possible to the user's skin as a result of its arrangement above the absorbent pad. In addition, since the elasticised distal edge of each flap is situated substantially above the proximal edge, the distal edges of both flaps are sufficiently far from each other and can follow the user's movements in an optimal manner, thus allowing the flaps always to maintain their barrier effect. Furthermore, the proximal edge of the flaps is at a maximum distance from the lengthwise elastic members fastened to the outer support sheet, and this makes the flap largely independent in relation to the other parts of the diaper, especially the absorbent pad and the lengthwise elastic members fastened to the support sheet.
Within the scope of the invention, each flap can be folded back onto itself outwards or, preferably, inwards. In the latter case each flap by itself forms a pouch in the crotch part when its elasticised distal edge is raised in relation to its proximal edge, that is to say in relation to the cover sheet, thus improving the barrier effect.